Gabriel Antillon uses a BACtrack Mobile Pro breathalyzer to check what his BAC level is during a demonstration event at The Tavern Downtown on Aug. 16, 2017, in Denver, Colorado. CDOT and law enforcement are hoping the use of personal breathalyzers will help reduce the number of repeat DUI offenders. Photo by Seth McConnell, YourHub.

Gabriel Antillon squeezes Natalie Letkey's shoulders after seeing what her BAC level was after using a BACtrack Mobile Pro breathalyzer during a demonstration event at The Tavern Downtown on Aug. 16, 2017, in Denver. Photo by Seth McConnell, YourHub.

Sam Stavish, right, shows Teresa Ly what her BAC level is after using a BACtrack Mobile Pro breathalyzer during a demonstration event at The Tavern Downtown on Aug. 16, 2017, in Denver. Photo by Seth McConnell, YourHub.

Polo Navarro blows into a BACtrack Mobile Pro breathalyzer during a demonstration event at The Tavern Downtown on Aug. 16, 2017, in Denver. Photo by Seth McConnell, YourHub.

Gabriel Antillon holds Natalie Letkey's hand after seeing what her BAC level was after using a BACtrack Mobile Pro breathalyzer during a demonstration event at The Tavern Downtown on Aug. 16, 2017, in Denver. Photo by Seth McConnell, YourHub.

Seth McConnell, YourHub

Becca Wiley blows into a BACtrack Mobile Pro breathalyzer during a demonstration event at The Tavern Downtown on Aug. 16, 2017, in Denver.

BACtrack founder and CEO Keith Nothacker holds up a BACtrack Mobile Pro breathalyzer during a press conference at The Tavern Downtown on August 16, 2017, in Denver. Photo by Seth McConnell, YourHub.

Nearly one-third of all fatal crashes in Colorado involve an alcohol-impaired driver, according to the Colorado Department of Transportation.

Last year, law enforcement officers across the state cited more than 21,000 drivers on suspicion of driving under the influence. Nearly 40 percent of those drivers already had at least one DUI citation.

To reduce the number of impaired drivers, CDOT and BACtrack, a personal breathalyzer company, are teaming up. The initiative is called “Before You Go, Know,” a first-of-its-kind, six-week campaign, in which pocket-sized breathalyzers are handed out as safety devices to Colorado drivers who have already been convicted of driving under the influence.

“You have a speedometer in your car to prevent you from speeding. Why wouldn’t you have something on your person to prevent you from drinking and driving?” said Sam Cole, safety communications manager at CDOT.

BACtrack gave 475 DUI offenders personal breathalyzers this month, in exchange for information about whether the device thwarts possible DUI incidents. Officials hope people will learn to judge their blood-alcohol content and whether they can drive safely. Another takeaway is to gain insight into the thought processes of people who drink and drive.

More than 150 residents of Jefferson and Adams counties are participating. Thirty-seven people died from alcohol-related traffic crashes in the two counties in 2016. There were 17 alcohol-related traffic deaths in Jefferson County in 2015, more than any other county in Colorado. CDOT highway safety manager Glenn Davis attributed the high number of traffic deaths in Jefferson County to its heavily used roads, whereas Cole says the Jeffco deaths could be the result of a spike in motorcycle crashes.

“A lot of motorcycle crashes involve impaired drivers,” he said.

Organizers initially aimed to involve 200 DUI offenders from Jefferson, Adams and Weld counties in the “Before You Go, Know” campaign, but it has grown to include nearly 500 offenders across Colorado.

“These are people who no longer have an interlock system or a suspended license. They’re on the roadways driving,” Cole said.

In Colorado, a blood-alcohol content of 0.08 or more is considered too high to drive and is the threshold for issuing a DUI charge; 0.05 is the threshold for issuing a charge of driving while ability impaired.

“We did a pilot study last year (in Colorado),” BACtrack founder and CEO Keith Nothacker said during a press conference Aug.16. “We got BACtrack breathalyzer devices into the hands of people and the results were amazing. Eighty-four percent of people who had the devices said that it reduced their likelihood to drive while impaired.”

The breathalyzer, called the BACtrack Mobile Pro, has the same accuracy as devices used by law enforcement officers, Nothacker said. But it is much smaller and connects with a smartphone via Bluetooth to display the user’s blood-alcohol level, the time at which their BAC will return to zero and an option to call Uber if the machine registers high intoxication. Users can guess their BAC before taking the test as a way of comparing their perception to reality. This feature helps users understand the way their bodies absorb alcohol.

The program kicked off as CDOT begins its annual Labor Day DUI crackdown, Cole said. Seven people died in alcohol-involved crashes during the three-day Labor Day weekend in 2016.

“We want to get that number down to zero through the use of breathalyzers and a strong law enforcement presence on our roadways,” Cole said.

Local residents were allowed to try out, look at and ask questions about the breathalyzers at the press conference. Not everyone believed the personal breathalyzers are a likely solution to the problem of people driving under the influence.

“Making (breathalyzers) accessible is nice, but how often are people going to remember it, and how often are people going to use them?” George Verbrugge, restaurant patron, said.

Through September, BACtrack is running a 20 percent discount and free shipping on the BACtrack Mobile Pro breathalyzer ($100) with the inclusion of the code “CDOT” at checkout. See details online at BACtrack.com.

For more information about the “Before You Go, Know” campaign, visit bit.ly/1TpJYcY.

Details about the ongoing campaign will be available in late September.